US Army, Technical Manual, TM 5-4120-243-14, AIR CONDITIONER, HORIZONTAL, COMPA 18,000 BTU, 208 V, 3 PHASE, 50-60 HERTZ; HARVEY W. HOTTEL MODEL CH20-6-08 (NSN 4120-00-411-3730), AMERICAN AIR FILTER MODEL AACH-618-2, (4120-01-177-5989), 208V, 3 PHASE, 400 HERTZ; TRANE MODEL MAC4H18-208-1201-03 (4120-00-411-3731), HARVEY W. HOTTEL MODEL CH20-4-08, (4120-00-383-3571), KECO MODEL KIF-18H-4, (4120-01-177-5990), military manuals